1. Technical Field
The present invention relates in general to the field of computers, and in particular to multiple blade servers housed in a server chassis. Still more particularly, the present invention relates to a method and system for a providing a virtual communications port to servers, in the server chassis, that do not have a real communications port.
2. Description of the Related Art
Server blade computers offer high-density server boards (blades) in a single server blade chassis (blade center chassis). A typical server blade computer is illustrated in FIG. 1, identified as server blade chassis 102. Server blade chassis 102 includes multiple hot-swappable server blades 104a-n. There are typically fourteen server blades 104 in server blade chassis 102. The operations of server blades 104 are coordinated by logic identified as management modules 108, each of which typically includes a processor for controlling input/output (I/O) functions, and allocating jobs and data to the different server blades 104. Typically, a first management module 108a is designated as the primary management module, and a second management module 108b is a back-up to be used if the primary management module 108a should fail. Another function of management module 108 is to control a power module 110 and cooling fans 112.
While communication to server blades 104 is typically possible via switches (not shown), many processes, such as remote consoles and debuggers that run under Linux™ and Windows™ require a serial communications port (“COM port”). These processes communicate with service processors (not shown) in the server blades. These service processors need to be accessed by the processes via a serial COM port. However, server blades 104 in a server blade chassis 102 do not have individual COM ports, primarily due to the integrated nature of the server blade chassis 102. A potential solution to this problem would be to have all server blades 104 share a common COM port on a backplane (not shown) in the server blade chassis 102. However, this solution is problematic since only one of the fourteen server blades 104 would be accessible at any give time.
What is needed, therefore, is a method and system that allows all server blades 104 in a server blade chassis 102 to be connected to an external COM port, and to allow simultaneous communication sessions to be established with each server blade 104. The method and system should be able to handle higher bandwidth requirements for Video redirect and code upgrades, as well as other data intensive communications.